Pump



Oct. 10, 1944. w. F. THOMPSON PUMP Filed Aug. 14, 1945 INV ENTOR.

ATTORNEY Patented Oct. 10, 1944 PUIVIP Willis F. Thompson, Portland, Maine, assignor to The Alden Speares Sons 00., Cambridge, Mass., a corporation of Massachusetts Application August 14, 1943, Serial No. 498,689

6 Claims.

The invention relates to a pump especially adapted for the delivery of corrosive liquids from containers, or carboys.

The object of the invention is to provide a pump of the specified character which will inherently function to safeguard the operator whatever may be the degree of internal pressure developed within the pump. For efi'ecting the pumping operation, the pump is provided with a piston operated by a piston rod. The piston operates within a cylinder, with the piston rod, which actuates the piston, extending outside the cylinder through a gland open to the atmosphere and through which gland the piston rod slides. It is the especial object of my invention to prevent the escape of liquid through this joint by relieving the joint of all pressure which might effect an escape of the liquid through it however fast the pump may be operated, and this Without affecting the proper action of the pump.

The invention can best be seen and understood by reference to the drawing in which- Fig. 1 shows the pump in vertical section, the top of a container or carboy to which the pump is applied being shown in broken lines.

Fig. 2 is a view partly in vertical section and partly in side elevation, of the top end portion of the pump.

Fig. 3 is a cross section on the line 3-3 of Fig. 1; and

Fig. 4 is a View, partly in vertical section and partly in side elevation, of a portion of the pump with contained piston.

Referring to the drawing: l represents an outside tubular casing, or jacket, the top end of which is closed, in manner later to be described. The jacket is provided with a contracted bottom end 2 from which extends a tubular extension 3. This extension is adaptable to enter and protrude into the top end, or mouth, of the conhas been secured between the outside jacket and the container. The cylinder is of lesser diameter than that of the jacket; its bottom end B is spaced from the bottom end 2 of the jacket;

and the pipe extension 9 from the bottom end 7 of the cylinder is of lesser diameter than the internal diameter of the jacket extension 3. Thus a chamber or passage ID is obtained extending from the top of the cylinder with open entry into the chamber of the container or carboy. The spacing of the cylinder within the jacket may be obtained in any suitable manner, as by providing the cylinder with external protuberances or bosses H which will operate not only to hold the cylinder properly spaced from the jacket, but will also operate to snugly maintain it within the jacket. The bottom contracted end 8 of the cylinder, around the point of entrance from the chamber 1 of the cylinder into the passage through the pipe 9, is provided with a valve seat I! upon which normallyrests an inwardly opening ball valve l3. This valve is caged in the bottom end of the cylinder between its contracted end 8 and the piston, later to be referred to, the contracted end of the cylinder being provided with an inclined face I4 by which the valve will be directed to normally maintain tainer, or carboy, 4, and become attachable thereto in the manner of a stopper by means of a collar 5 which snugly embraces the extension 3 of the jacket with top bearing against the contracted bottom end 2 thereof. The collar 5 is made slightly bevelled in order that itmay accommodate itself to mouths of different sizes, and fit snugly within any mouth within which it is contained.

6 represents a cylinder having a chamber T within which reciprocates a piston, as will later be referred to. The cylinder is provided with a contracted bottom end 8 from which extends a pipe extension 9 of sufiicient length to extend to the bottom of the container when attachment a closed position.

Surmounting the jacket, and with normal bearing against the top edge thereof, is a cap l5 to the head of which is secured a piston rod it, the cap forming a hand grip by which the piston rod is reciprocated. The cap is of substantially the same diameter as the jacket, and the jacket forms a stop for limiting the down thrust of the piston rod through engagement of the bottom edge of the cap with the top edge of the jacket. The top end of the cylinder 6 is closed by a displaceable cover H. The piston rod passes through this cover.

The piston comprises an internal sleeve I8 slidable within the cylinder and with which cooperates both an annular head IS on the lower end of the piston rod and a pin 20 passed laterally through the piston rod. The pin lies above the sleeve; the head below it. The head is of lesser diameter than the interior diameter of the cylinder. Both the head and pin, however, are of sufficient diameter and length, respectively, that they will engage the sleeve for moving it within the cylinder when the piston is reciprocated. The head and pin are spaced from each other a distance longer than the length of the sleeve so that when the piston rod is raised its annular head l9 will be brought into engagel at a point'adjacent its top edge. 25, keeper and pistonrod form a top closure ment with the bottom edge of the sleeve l8 and make closed engagement therewith. Accordingly, as the piston rod is drawn up, the sleeve will be moved upwardly within the cylinderby the drawing engagement of the head, and the combined head and sleeve then operating as a piston, will induce a partial vacuum in the chamber of the cylinderbelow the piston causing 1 liquidin the container to enter by way of the pipe 9, opening the valve I3, and filling the chamber of the cylinder up to the point of the ascending piston. Upon the return of the piston through lowering of the piston rod all upward flow of liquid from the container will cease, the

' valve [3 will resume its normal closed position,

the head l9 will separate from the sleeve, thercby forming communication throu'gh the piston,

and the pin 20 will be brought into engagement with the sleeve, moving it downwardly through the cylinder to the limit of the downward stroke ofthe piston rod. During this downward movement of the piston rod the piston rodandpiston will pass through the column of liquid which has been drawn into the chamber of the. cylinder and which is kept therein by the closure of the 'valve l3, whereupon this column of liquid ,will bedisplaced in part by the descending partsincluding especially the piston rod, and the amount of liquid thus displaced will flow out of thecylinder chamber through a spout 21, which is connected to the cylinder near its top and proceeds outwardly through the passage 10 and through the jacket. When the pistonis again raised liq-.- uid will be drawn'into the chamber of the cylinder below the piston'the same asbefore, and

at the same time all undispla'ced liquid lying above the piston will be forced to outlet through the spout.- Thus the pump is a double-acting pump causing flow of fluid from the spout durs ing both the upward and downward stroke of 'the'piston.

.As previously explained, the top end of the cylinder is closed by a displaceable cover II. This cover is held in its normal position of clo-- sure by a keeper.23 through which the piston rod extends. The jacket is, longer than the cylinder, extending above the covered top end of the cylinderforming a chambr24. The keeper is located in part within this chamber and in partwithin the chamber of the cap I5. The

, keeper is fixedly connected to the jacket by an annular flange 25 which connects with the jacket The flange for. the chamber 24, which closure is further supplemented by a packing 26 locatedwithin a suitable packingfgland formed within the keeper and through which gland the piston rod extends.

Little Or nopressure can be developed in the chamber 24 inasmuch as this chamber is in open communication with .thepassage I which leads I back into the chamber-of the carboy as previously explained. Accordingly liquid admitted tothis chamber will flow back into the-container or carboy, The cover is displaceable by, pressure generated from within thecylinder duringthe pumping operation. This pressure will tend to open the cover a sufiicient amount torelieve the.

pressure and liquid will flow by thecover from out of-the cylinder into the'c'hamber 24 andbe 3 returned to the containeror carboy. The displaceability of the cover is efiected by making I the cover of some Stififbllt elastic material. The keeper is formedto have a broad diametric' bearing against the cover enabling the oppositesides of the cover to bend upwardly, opening the cover when subjected to pressure developed within the cylinder. The opposite sides of the cover are allowed to bend only in an amount sufficient to relieve .the pressure, any excess bending being prevented by the bevelled bottom faces 21 of the keeper against which the turned or bent sides of the cover when displaced may have bearing. In ordinary operation the cover will be displaced but little, if any. In any event, however much the cover is displaced to allow the escape of liquid it will not affect the proper action of the pump. With the pressure within the cylinder thus relieved no pressure canbe generated, however fast the pump may be operated, which will permit of an escape of liquid through the packed glandjin the keeper through which the piston rod is passing, this being the only gland open to the atmosphere which might endanger the operator if any liquid is permitted to escape through it. I

i In order that the liquid may not continue to drip from the spout after the pumping operation has been completed the cylinder at a point just below the entrance to the spout is provided with an opening 28; After the pumping operation of the liquid has been completed liquid remain ing in the top of the pump and spout will be enabled to flow back through thisopening into the passage 10 and be returned to the carboy. The opening 28 in the cylinder possesses the further advantage of assisting in relieving pressure within the cylinder. Theopening, however, is so small as not to interfere with a proper delivery of fluid through the outlet, or spout, during the pumping operation;

jacket inclosing the cylinder andco-operating" therewith to form a chamber overlying the end of the cylinder with open passageleading therefrom for the return into the container of liquid admitted to the chamber, means afiixed to the jacket providing a top closure for the chamber and in-- eluding a packed gland open to the atmosphere through which the reciprocable element extends,

means for preventing an escape of liquid through said gland during the operation of the pump including a displaceabl cover for the end of said cylinder, which cover. is located at the bottom of said chamber, and through which cover the reciprocable'element extends, said cover being displaceable by liquid pressure generated within the cylinder whereby upon displacement of the cover liquid will escape from the. cylinder into said chambe and passage leading therefrom'and be returned to the container, and means for retaining the displaceable cover in a normal closed position.

2. In a pump the combinationcomprisinga cylinder with delivery outlet for liquid drawn into the cylinden m eans whereby liquid maybe drawn into the cylinder including'a reciprocable element, a jacket inclosing the cylinder and cooperating therewith to form 'a chamber overlying the end of the cylinder With'open'passage leading-therefrom for the escape of liquid ad mitted 'to the chamber, means ailixed 'tothe jacket providing a top closure for the chamberextends, means for preventing an escape of liquid through said gland during the operation of the pump including a displaceable cover for the end of said cylinder, which cover is located at the bottom of said chamber, and through which cover said reciprocable element extends, said cover being displaceable by liquid pressure generated within the cylinder whereby upon displacement of the cover liquid will escape from the cylinder into said chamber and passage leadin therefrom, and means for retaining the displaceable cover in a normal closed position.

3. In a pump the combination comprising a cylinder with delivery outlet for liquid drawn into the cylinder, means whereby liquid may be drawn into the cylinder including a reciprocable element, means inclosing the cylinder and cooperating therewith to form a chamber overlying the end of the cylinder with open passage leading therefrom for the escape of liquid admitted to the chamber, said inclosing means providing also a top closure for said chamber and including a packed gland open to the atmosphere through which said reciprocable element extends, means for preventing an escape of liquid through said gland during the operation of the pump including a displaceable cover for the end of said cylinder, which cover is located at the bottom of said chamber, and through which cover said reciprocable element extends, said cover being displaceable by liquid pressure generated within the cylinder whereby upon displacement of the cover liquid will escape from the cylinder into said chamber and passage leading therefrom, and means for retaining the displaceable cover in a normal closed position.

4. In a pump the combination comprising a cylinder with delivery outlet for liquid drawn into the cylinder, means whereby liquid may be drawn into the cylinder including a reciprocable element, means inclosing the cylinder and cooperating therewith to form a chamber overlying the end of the cylinder with open passage leading therefrom for the escape of liquid admitted to the chamber, said inclosing means providing also a top closure for said chamber and including a packed gland open to the atmosphere through which said reciprocable element extends, means for preventing an escape of liquid through said gland during the operation of the pump including an elastic cover for the end of said cylinder, which cover is located at the bottom of said chamber, and through which cover said reciprocable element extends, said elastic cover being displaceable by the bending thereof by liquid pressure generated within the cylinder whereby upon displacement of the cover liquid will escape from the cylinde into said chamber and passage leading therefrom, and means for retaining the displaceable cover in a normal closed position comprising a keeper engaging the cover and with relationship to which said cover may bend when displaced as aforesaid.

5. In a pump the combination comprising a cylinder with delivery outlet for liquid drawn into the cylinder, means whereby liquid may be drawn into the cylinder including a reciprocable element, a jacket inclosing the cylinder and cooperating therewith to form a chamber overlying the end of the cylinder with open passage leading therefrom for the escape of liquid admitted to said chamber, a cap surmounting the jacket with normal bearing against the top edge thereof and to the head of which cap said reciprocable element is secured whereby said element may be reciprocated by one grasping said cap, a closure for the top of said jacket and chamber overlying the end of said cylinde as aforesaid, said closure having within it a packed gland through which said reciprocable element extends, and means displaceable by liquid pressure generated within said cylinder for closing the top end thereof whereby liquid may escape from the cylinder into said chamber and passage leading therefrom and liquid pressure be excluded from said gland.

6. In a pump the combination comprising a cylinder with delivery outlet for liquid drawn into the cylinder from the container, means including a reciprocable element whereby liquid may be drawn into the cylinder from the container and deliver through said outlet, a jacket inclosing the cylinder and co-operating therewith to form a chamber overlying the end of the cylinder with open passage between the cylinder and jacket leading from said chamber for the return into the container of liquid admitted to the chamber, means afiixed to the jacket providing a top closure fo said chamber and including a packed gland open to the atmosphere through which the reciprocable element extends, a displaceable cover for the end of said cylinder and through which cover the reciprocable element extends, said cover being displaceable by liquid pressure generated Within the cylinder, means for retaining the displaceable cover in a normal closed position, said cylinder being provided with an opening to said open passage, said opening being located below its delivery, outlet whereby pressure within the cylinder will be lessened during the pumping operation and liquid remaining in the cylinder and delivery outlet after the pumping operation will drain through said opening and drip from said delivery outlet be thereby obviated.

WILLIS F. THOMPSON. 

